The Exterior Viewpoint

This upbeat novel concerns a group called the Church of Enlightenment.

Two members, George and Jennifer, go on the first expedition to Mars, where they are marooned. Running out of oxygen, they discover a milelong sentient starship inside the Face.

Meanwhile, on Earth, a group of alien beings have been taking over the bodies of influential individuals and using them to conduct a war against humans.

Attacked by the aliens, George, Jennifer, and the other Church members flee on the starship to another planet, where they develop superhuman powers, and return to defeat the aliens.